Brush-holder for dynamo-electric machines.



No. 741,945. PATENTED OCT. 20, 1903. M. E. THOMPSON.

BRUSH HOLDER FOR DYNAMO ELECTRIC MACHINES. APPLICATION FILED MAR. s.1903.

N0 MODEL.

Witnesses: I Inventor ELMRsW [W W w .sw, M, S (SJAW- Attorney m: Normsawns cc. PHOTOUTHD 'AASMINGTON, n c.

, UNITED STATES Patented October 20, 1903.

PATENT OFFICE.

MILTON E. THOMPSON, OF RIDGVVAY, PENNSYLVANIA.

BRUSH-HOLDER FOR DYNAMO-ELECTHIC MACHINES.

BPECIFICATION forming part of Letters Patent No. 741,945, dated October20, 1903.

Application filed March 6, 1903. Serial No. 146,436. (No model.)

holder exemplifying my invention, the same being illustrated as inworking position upon its supportingstud; Fig. 2, a plan of the same,and Fig. 3 a side elevation of the same in latched-up unclampedcondition.

The object of myinvention is to produce a brush-holder readily detachable from its support, detachable without the use of tools, tietachableby the use of one hand only independent of rubbing contacts forconductivity, and readily adjustable for staggering relationship on thecommutator.

In the drawings, 1 indicates a stud of rec- 4 tangular cross-section tocarry the brushholder; 2, a flange at the inner end of the stud to servein attaching it to its support; 3, a plate lying against the front faceof the stud and projecting from one edge thereof toward the commutatorwith which the brush is to cooperate; 4, a shallow recess in the backplate 3, where the plate engages the face of stud 1; 5, the upper shoreof this recess engaging the upper edge of the stud and having a rearwardprojection of any desired extent upon the upper edge of the stud; 6, thelower shore of the recess 4:,engaging the lower edge of the stud andhaving but little projection, merely enough to properly position theplate upon the stud; 7, the lugs projecting forwardly from the upper endof plate 3; 8, the brush, illustrated as a rectangular block of carbon,with its rear face seating against the front face of the lower portionof plate 3, its lower face being adapted to make contact with thecommutator with which the brush is to cooperate; 9, the carbon-carrier,being a metallic block seated upon the top of the brush and having sideflanges embracing its front and rear faces, this carrier being bypreference soldered to the brush, the back of the brush and carrierlying fairly against the front face of the lower portion of plate 3; 10,a pair of studs screwed into carrier 9 and extending upwardly throughguiding-eyes in lugs 7; 11, helical springs surrounding these studs andacting under compression between lugs? and the carrier of the brush andtending to urge the brush downwardly; 12, a yoke attached to the upperends of the two studs; 13, a lead in flexible bow form, having its lowerend secured by a screw to the upper surface of brush-carrier 9, itsupper end being secured against the front face of the upper portion ofplate 3, this lead being formed, preferably, of several thicknesses ofthin metal; 14, a stiff bow-spring, with its bow upward, its front endbeing secured to the front of the upper portion of plate 3, preferablyoverlying lead 13, the rear end of this spring coming behind stud 1 atabout its center of width and bent to form a bearing-eye; 15, afinger-cam journaled in the bearing-eye at the rear end of spring 14 andadapted, when the handle is turned down to active position, to bearagainst the rear face of stud 1 and firmly clamp the brush-holder to thestud with such power as may be due to the stiffness of spring let, thiscam being adapted when turned up to the idle position indicated in Fig.3 to stand entirely free from stud 1; 16, a springtrigger securedagainst the outer face of the front portion of spring 14 and projectingupwardly to the rear of yoke 12, its latch portion being adapted tospring under the yoke when the brush is pulled upwardly away from thecommutator; 17, the screws securing the spring-trigger, the spring 14:,and lead against the front face of plate 3, and 18 lugs projectingforwardly from plate 3 and loosely encircling the studs and theirsprings, these lugs being located at such height as not to interferewith the rising of the brush to latching position.

In Fig. 3 the device is shown with the brush latched in upward positionand with the cam in un'clamping position. Assume the handle of the camto be turned downward, thus firmly but elastically clamping thebrushholder to stud 1, and assume trigger 16 released, so that springs11 will force the brush downward to about the position indicated in thedotted lines in Fig. 3. The brush will thenbearuponthecommutatorand bepressed thereto by the springs 11. The commutator is to run in suchdirection as to urge the brush against the lower portion of plate 3.While the brush and its carrier have a good contact bearing againstplate 3, such bearing is not depended upon for the conductivity, thelead 13 serving as a positively-connected conductor between the brushand the body of the brush-holder.

I have used the terms front, rear, upper, and lower; but it should beunderstood that these terms are merely relative, for these brush-holdersare to be employed as usual-that is to say, arranged in a circle aroundthe commutator. It is furthermore to be understood that while thedrawings show but one brush-holder arranged upon the stud 1 a singlestud may carry a number of the brush-holders. Indeed it is my practiceto employ as many as eight of the brush-holders upon a stud, the studbeing of appropriate length. It is to be observed that the brushholdermay be placed at any point along the length of the stud, and it followsthat where each stud supports a plurality of brush-holders thebrush-holders are quite apt without any deliberate intent to that end tobecome staggered in their relationship to each other and in theirbearing upon the commutator, or, in other words, the brushes areself-inclined to break joint with each other.

Attention is now to be called to the following practical points inconnection with this structure: First, the conduction between the brushand plate 3 is independent of the charactor of sliding contact betweenthe brush and the plate, the lead 13 furnishing a positively-eonnectedconductor; second, contact between plate 8 and stud 1 is a fair and firmone, the cam serving as a means for bringing the surfaces of these partsinto contact with a yielding but powerful pressure; third, the devicewithout modification in form is adapted for right or left hand usethatis to say, giving consideration to Fig. 3, the brush is at the left ofthe stud, thus adapting the device to a commutator turning in clockwisedirection, but the mere placing of the structure upon the opposite sideof the stud would adapt it to an armature running in the oppositedirection; fourth, the fact that the brush-holder is attached to itsstud by mere clamping and without any doweling or the like it followsthat the brush-holder may not only be adjusted as desired along thelength of the commutator, but that, as before explained, the brusheswould be selfstaggering; fifth, the general structure is comparativelynarrow, thus furnishing superior facility for the grouping of amultiplicity of them upon a single stud; sixth, as the brush-holder isheld to its supportingstud by means of the clamping-cam only it followsthat it can be removed from its stud without the use of tools; seventh,the form of the structure as regards spring 1e and cam 15 is such thatthe cam may be released and the structure withdrawn from itssupporting-stud by the use of one hand, thus rendering the device verysafe; eighth, the structure when in hand and separated from its supportlends itself well to the hand, somewhat after the order of apistol-grip, and may thus be readily and conveniently put into positionwhile a machine is running; ninth, this quality peculiarly adapts theholder to being withdrawn from or placed into association with groups ofsimilar structures; tenth, as positioning-shoulder 6 has but littleprojection as compared with shoulder 5 the structure requires but atrifle of forward displacement in being disengaged from its stud, thuspermitting the outer radial movement of the structure in the act ofwithdrawal and guarding against its inward movement into inadvertentconflict with the commutator; eleventh, the brush-holder being separatedfrom the machine and in hand the brush may be latched in retractedposition and then the structure applied to the machine, the latch beinglater released, thus guarding against accidental premature contactbetween the brush and the commutator; twelfth, the structure having beenplaced in position on the machine in latched-up condition a mere touchof the finger releases the latch and permits the brush to go intocontact with the commutator; thirteenth, the form of the structure inwhich the brushholder seats against the substantially radial face of thesupporting-stud permits the removal and application of the ln'ush-holderfrom and to the machine in a substantially radial direction free frominterference with contiguous ln'ush-holders.

It should be mentioned that lugs 18 are not essential, but that they areuseful in preventing forward displacement of the brush, &c., in case ofaccidental turning of the commutator in reverse direction.

This device is in practice almost universally employed in connectionwith carbon brushes, and it is only in connection with such brushes,thatthe carrier 9 becomes essential. In other words, the brush and itscarrier may be viewed practically as one item, which may well be spokenof as the brush. The brush proper is the perishable portion of thedevice,and provision is made for its ready replacement, it being onlyrequisite to unscrew studs 10 and the screw at the foot of lead 13 fromthe brush and substitute a new brush, the carrier being thrown away withthe old brush or used as a mounting for another brush.

1 claim as myinvention- 1. In a brush-holder, the combination, substantially as set forth, of a plate having an attaching-surface atsubstantially right angles to the active face of the brush and adaptedfor engagement with the face of a supporting-stud, a clamping devicecarried by said plate and serving to grip the opposite faces of thesupporting-stud, a brush mounted for movement on said plate in adirection sub stantially parallel with said attaching-surface, and aspring arranged to press the brush to its work.

2. In a brush-holder, the combination, substantially as set forth, of aplate having a recessed attaching surface at substantially right anglesto the active face of the brush and adapted for engagement with the faceof a supportingstud,shoulders upon said surface to engage the oppositeedges of the stud, a clamping device carried by said plate and servingto grip the opposite faces of the supporting-stud, a brush mounted formovement on said plate in a direction substantially parallel with saidattaching-surface, and a spring arranged to press the brush to its work.

3. In a brush-holder, the combination, substantially as set forth, of aplate having an attaching-surface at substantially right angles to theactive face of the brush and adapted for engagement with the face of asupporting-stud, an elastic clamping device carried by said plate andserving to grip the opposite faces of the supporting-stud, a brushmounted for movement on said plate in a direction substantially parallelwith said attaching-surface, and a spring arranged to press the brush toits Work.

4. In a brush-holder, the combination, sub stantially as set forth, of aplate having an attaching-surface at substantially right angles to theactive face of the brush and adapted for engagement with the face of asupporting-stud, a bow-spring fixed to said plate and arranged tostraddle the supporting-stud, a clamping device carried by the free endof the spring and adapted to engage the rear face of thesupporting-stud, a brush mounted for movement on said plate in adirection substantially parallel with said attachingsurface, and aspring arranged to press the brush to its Work.

5. In a brush-holder, the combination, substantially as set forth, of aplate having an attaching-surface at substantially right angles to theactive face of the brush and adapted for engagement with the face of asupporting-stud, a bow fixed to said plate and straddling theattachingstud, a cam pivoted to the free end of said bow and adapted toengage the rear face of the attaching-stud, a brush mounted for movementon said plate in a direction substantially parallel with saidattaching-surface, and a spring arranged to press the brush to its work.

6. In a brush-holder, the combination, substantially as set forth, of aplate having an attaching-surface at substantiallyright angles to theactive face of the brush and adapted for engagement with the face of asupporting stud, a bow-spring fixed to said plate and straddling thesupporting-stud and having a bearing formed in its rear end at the rearof the stud, a cam pivoted to said bearing-eye and adapted to engage therear face of the stud, a brush mounted for movement on said plate in adirection substantially parallel with said attaching-surface, and aspring arranged to press the brush to its work.

7. In abrush-holder, thecombination, substantially as set forth, of aplate having an attaching-surface at substantially right angles to theactive face of the brush and adapted for engagement with the face of asupportingstud and provided with a brush-resisting projection downwardlybeyond the lower edge of said stud, a clamping device carried by saidplate and serving to grip the opposite faces of the supporting-stud, abrush mounted for movement on the brush-resisting projection of saidplate in a direction substantially parallel with said attaching-surface,and a spring arranged to press the brush to its work.

8. In a brush-holder, the combination, substantially as set forth, of aplate having an attaching-surface at substantially right angles to theactive face of the brush and adapted for engagement with the face of asupportingstud, means for securing said plate to the supporting-stud, abrush mounted for movement on said plate in a direction substantiallyparallel with said attachingsurface, a spring arranged to press thebrush to its work, and atrigger arranged to serve in latching the brushin retracted position upon the plate.

9. In a brush-holder, the combination, substantially as set forth, of aplate having an attaching-surface at substantially right angles to theactive face of the brush and adapted for engagement with the face of asupportingstud, a clamping device carried by said plate and serving togrip the opposite faces of the supporting-stud, a brush mounted formovement on said plate in a direction substantially parallel with saidattaching-surface, a flexible lead having one end secured to said brushand the other end secured to said plate, and a spring arranged to pressthe brush to its work.

10. In abrush-holder, the combination, sub stantially as set forth, of aplate having an attaching-surface at substantially right angles to theactive face of the brush and adapted for engagement with the face of asupportingstud, a clamping device carried by said plate and serving togrip the opposite faces of the supporting-stud, a brush mounted formovement on said plate in a direction substantially parallel with saidattaching-surface, a flexible lead in how form having one end connectedwith the brush and its other end connected With said plate and havingits bow projecting outwardly from the front face of the plate, and aspring arranged to press the brush to its work.

11. In a brush-holder, the combination, sub stantially as set forth, ofa plate having an at taching-surface at substantially right angles tothe active face of the brush and adapted for engagement with the face ofa supportingstud, means for securing the plate to the sup porting-stud,a plurality of perforated lugs projecting from the upper forward portionof the plate, studs sliding each in a pair of said perforations parallelwith the plate, a brush secured to the lower end of the studs, andhelical springs disposed upon the studs between the lugs and the brushand serving to urge the brush to its work.

12. In a brush-holder, the combination, substantially as set forth, of aplate having an attaching-surface at substantially right angles to theactive face of the brush and adapted for engagement with the face of asupportingstud, means for securing the plate to the supporting-stud,perforated lugs projecting from the upper forward portion of the plate,studs sliding in said perforations parallel with the plate, a brushsecured to thelower end of the studs, helical springs disposed upon thestuds between the lugs and the brush and serving to urge the brush toits work, a yoke connecting the upper ends of the studs, and aspringtrigger fixed to the plate and serving to engage under the yokeand retain the brush in retracted position upon the plate.

13. In a brush-holder, the combination, substantially as set forth, of aplate having an attaching-surface at substantially right angles to theactive face of the brush and adapted for engagement with the face of asupportingstud, means for securing the plate to the supporting-stud, abrush lying against the lower front portion of the plate, a plurality ofperforated lugs projecting from the upper front portion of the plate,studs sliding each in a pair of said perforated lugs parallel with theface of the plate and having their lower ends separably screwed into thebrush, and helical springs upon the studs between the brush and saidlugs and serving to urge the brush to its Work.

14. In a brush-holder, the combination, substantially as set forth, of aplate having an attaching-surface at substantially right angles to theactive face of the brush and adapted for engagement with the face of asupportingstud, means for securing the plate to a supporting-stud, abrush lying against the lower front portion of the plate, abrush-carrier secured to the brush, a plurality of perforated lugsprojecting from the front upper portion of the plate, studs sliding eachin a pair of said perforated lugs parallel with the face of the plateand having their lower ends separably secured in said carrier, andsprings engaging between said lugs and brush and serving to urge thebrush to its work.

15. In a brush-holder, the combination, substantially as set forth, of aplate having an attaching-surface at substantially right angles to theactive face of the brush and adapted for engagement with the face of asupportingstud, means for securing the plate to a supporting-stud, abrush lying against the lower front portion of the plate, abrush-carriersecured to the brush, perforated lugs projecting from thefront upper portion of the plate, studs sliding in said perforated lugsparallel with the face of the plate and having their lower endsseparably secured in said carrier, springs engaging between said lugsand brush and serving to urge the brush to its work, and perforated lugsprojecting forward from said plate above the carrier and encircling thestuds and springs.

16. In abrush-holder, the combination, sub stantially as set forth, of aplate having an attaching-surface at substantially right angles to theactive face of the brush and adapted for engagement with the face of asupportingstud, perforated lugs projecting from the face of the plate, abrush seated against the lower front face of the plate, studs sliding insaid perforated lugs parallel with the plate and having their lower endsengaging the brush, a flexible lead having one end attached to saidbrush and the other end lying against the face of the plate, abow-spring straddling the supporting-stud and having its front endsecured in front of said plate, a clamping device carried by the rearend of the spring, a yoke connecting the upper ends of the slidingstuds, a spring-trigger carried by the plate and adapted to engage theyoke when the brush is in retracted position, and helical springs uponthe sliding studs between said perforated lugs and the brush.

MILTON E. THOMPSON.

Witnesses:

R. G. EcoLEsToN, THos. M. MURPHY.

